Transducer



Nov. 22, 1960 H. E. SOSTMAN TRANSDUCER Filed Feb. 10, 1959 INVENTOR.

United States Patent TRANSDUCER Henry E. Sostman, Roselle Park, N.J., assignor to H. E Sostman 6?! 0a., Township of Cranford, NJ, a body corporate of New Jersey Filed Feb. 1t 1959, Ser. No. 792,366

Claims. (Cl. 338-176) My invention relates generally to transducers having a high resistance to disturbance of electrical contact therein under conditions of heavy vibration.

It is among the objects of my invention to provide a transducer that Will convert movement into variations in an electrical circuit.

It is another object of my invention to provide a transducer in which the various contacts at contact surfaces are disposed in general opposition to displacement due to being subject to heavy vibration.

A still further object of my invention is to provide a transducer in which a contact between a contact member and a resistor is achieved in cooperation with a plurality of contacts between contact strips and contact springs.

Yet another object of my invention is to provide a plurality of contacts in a transducer which include contact springs which resonate at different frequencies.

Yet another object of my invention is to provide a transducer having a driven member which may be responsive to a wide variety of actuating members responsive to a wide variety of forces exerted in various directions; such driven member is thereby subjected to generally axial reciprocation.

These objects and advantages, as well as other objects and advantages, may be achieved by the device shown merely by way of illustration in the drawings in which:

Figure 1 is a vertical sectional view of a transducer illustrating my invention;

Figure 2 is a top plan view thereof;

Figure 3 is a sectional view taken on the lines 3-3 in Figure 2, looking in the direction of the arrows;

Figure 4 is a vertical sectional view taken on the lines 4-4- in Figure 2, looking in the d irection of the arrows;

Figure 5 is a vertical sectional view taken on the lines 5-5 in Figure 2, looking in the direction of the arrows; and

Figure 6 is a view in perspective of the assemblage of elements disposed in displaced spacial relationship to each other.

Referring now to the drawings in detail, my transducer provides a base which has an aperture 12. A driven member or shaft 13 projects through the base through this aperture and is freely movable therein in a general axial direction perpendicular to the top of the base. Jewel bearings or other type bearing for the driven member or shaft may be mounted on the base to serve as a low friction surface for the driven member tomove on. Attached to the top of the base, there are a suitable number of posts 14, 15, 16 17 positioned generally to provide mountings for the various components. I have shown four although this number may be varied. One pair of these posts 15, 17 may be made of aluminum or of other suitable material to which there has been applied a dielectric dress, as by anodizing or by applying a coating substance. Applied to this pair of posts are contacts or contact strips 18, 18 of an electrically conductive material which, preferably, is resistant to deteri- 2,961,627 Patented Nov. 22, 1960 oration which might impair their conductivity. A lead 19 is attached to both of these strips.

Attached to the driven member 13 in a generally transverse manner is a plate 20. This plate is provided with bent-over ears on enlargements 21 along each of its top and bottom edges. These enlargements are disposed in general perpendicularity to the plane defined by the plate. Each of these ears is provided with a hole dimensioned to receive an insulating bushing 22. The insulating bush ing is attached to the ears by cement or some other suitable manner. The bushing is slid over the driven member and is attached thereto by a suitable sealing agent. Attached to the front of the plate is a generally elongated slider or brush 23. Formed along the top edge of this slider is a generally V-shaped contact surface 24 of elongated character, substantially co-extensive with the longitudinal dimension of the brush. integrally formed on the bottom edge of the slider are a pair of enlargements 25, 25 disposed at both ends thereof. These enlargements are attached to the plate by welding, or in some other suitable manner. Both the plate and the brush are of electrically conductive material. It is also preferred that the brush be made of material which is relatively resistant to deterioration which might impair conductivity and is formed of a material which is inherently resilient and relatively stifi so as to act as a firm spring contact.

Mounted on another post is a resistor 26. This resistor may be of uninsulated fine wire 27 relatively resistant to deterioration, wound on a glass rod 28 or a rod of some other suitable material. Other types of resistors may be used. The rod may be cylindrical, or have some other suitable shape which will cause the wire to present a generally elongated contact surface. Insulated wire may be used with the insulation removed from the contact surface. The rod may be of substantially the same cross-section throughout its entire length so that the resistance value of each turn of wire shall be the same, if such value change be desired, or the crosssectional dimensions of the rod may be varied throughout its length, so that resistance value per turn might alter from one turn to another, relatively increasing or decreasing. The resistor is mounted on an L-shaped bracket 29 by cement or in some other suitable manner. The bent over portion 30 is biased. The bracket 29 is attached to a mounting plate 31. The mounting plate is soldered or attached in some other suitable manner to a post. The bracket is arranged for angular variation in relation to its attachment to the plate so that the slider 23 and the resistor 26 shall not be disposed in parallelism with each other, ie in exact contact with each other along the entire length of their respective contact surfaces. Thus, there is an elongated mounting slot 32 which is elongated so that the screw 33 passing therethrough to engage the mounting plate with the bracket mav move within the slot and permit a variable angular deviation between the contact surface of the resistor and the contact surface of the slider. Another hole 34 provides a pivot point and accommodates a second screw 35.

Mounted on the back of the plate 20, there is a contact spring 36. This spring 36 is secured to the back of the plate between the enlargements, by welding or in some other suitable manner. The point of attachment is preferably at the general center of the back of the plate and at the center of the arms 33, 39 of the spring, although the arms of the spring are of disproportionate length. in the event of vibration of the transducer, the arms being of disproportionate length, they will not be in resonance at the same time and contact of at least one of the arms of the spring is assured. Adjacent to the point of attachment of the spring with the back of the plate, the spring is deformed outwardly on both sides of the point of attachment in the general direction of the contact strips. The ends of the spring define the arms 38, 39 which are deformed so as to have a generally arcuate configuration and present a generally convex contact surface in engagement with the contact strips. This spring is likewise formed of relatively resilient conductive material having a resistance to deterioration.

The .spring 36 serves to insure relatively continuous electrical contact with the contact strips and also prevents rotational deviations of the plate 20 and the slider 23 mounted thereon. The driven member 13 may react in response to a bellows or in response to another type of driving device. The movement of the driven member 13 will be transmitted to the spring 36 which will continuously engagethe contact strips 18, 18 by movement back and forth lengthwise along the contact strips in response to the movement of the driven member. Likewise, the slider 23 will present a contact surface in engagement with a portion of the elongated contact surface of the resistor 26. In response to the movement of the driven member 13, the slider 23 will move along the contact surface of the resistor 26. If the variably mounted resistor were disposed at 90 degrees to the slider, the motion of the driven member would have to be equal to the length of the resistor in order to cause the slider to wipe the entire contact surface of the resistor. On the contrary, if the resistors contact surface were disposed in parallelism with the contact surface of the slider, any movement of the driven member would open the contact of the slider with the contact surface of the resistor. If the angular deviation between the slider 23 and the contact surface of the resistor 26 is adjusted to an acute angle, it may be disposed within those limits and to be within the range of movement of the driven member 13, so that within such range of movement, the slider 26 will wipe from one end of the contact surface of the resistor 26 to the other end, thereby providing a continuous range of varying contacts with the contact surface of the resistor in response to any position of the driven member within its range of movement. By reason of the resilience of the slider 23, the plurality of contacts pro vided, and the fact that the arms 38, 39 resonate at different frequencies, vibration is relatively ineffective to impair the continuity of the electric circuits involved in this transducer. The circuit is established from the contact strips 13, 18 through the arms 38, 39 of the contact spring 36, through the plate 29, through the slider 23, to the resistor 26.

It is noted that although I have shown the slider to be mounted movably on the driven member, and the resistor to be mounted in a fixed manner (though adjustable), that these parts may be interchanged and the slider mounted stationary and the resistor mounted movably on or in response to the driven member.

It is further noted that although I have referred to a resistance, it is obvious that an inductance may be equallydesirable as a component to which variable contact is to be made, and of course, an inductance may be substituted for the resistance. The same applies to multipole switches. V It is further to be noted that a plurality of resistances and sliders may be mounted on a single driven member to provide a plurality of electrical responses to the movement of the driven member.

. The foregoing description is merely intended to illustrate an embodiment of the invention. The component parts have been shown and described. They each may have substitutes which may perform a substantially similar function; such substitutes may be known as proper substitutes for the said components and may have actually been known or invented before the present invention; these substitutes are contemplated as being within the scope of the appended claims, although they are not specifically catalogued herein.

I claim:

1. A transducer comprising a resistor, a generally elongated contact surface on the resistor, a conductive slider, a generally elongated contact surface on the slider, a portion of each of the contact surfaces 'in contact with the other, a driven member, a slider connected to the driven member, a pair of stationary conductive contacts, a conductive contact spring connected to the driven member and slidably engaged with both of the stationary contacts, and the slider and the contact spring electrically connected together.

2. A transducer in accordance with claim 1 in which the contact springs slidable engagement with both of the stationary contacts is made by portions of the contact spring defining arms of unequal length.

3. A transducer in accordance with claim 1 in which the contact surfaces of slider and of the resistor are disposed at an acute angle'to each other in generally parallel planes.

4. A transducer comprising a driven member, a contact spring defining a pair of contact arms extending in general perpendicularity to the axis of movement of the driven member, a pair of stationary contacts engaged with the arms for slidable contact as the arms move with the driven member, a slider attached to the driven member and extending in a generally opposite direction from the contact arms, and generally perpendicularly to the axis of movement of the driven member, a generally elongated contact surface on the slider, a resistor, a generally elongated contact surface on the resistor, the resistor contact surface disposed at an acute angle to the slider contact surface, and a portion of each of the contact surfaces in slidable contact with the other.

5. A transducer comprising a base, a resistor mounting post on the base, a resistor mounted on the resistor mounting post, a generally elongated contact surface on the resistor, a conductive resilient slider, a generally elongated contact surface on the slider, a portion of each of the contact surfaces in wiping contact with the other contact surface, a conductive plate connected to the slider, a driven member connected to the plate, a stationary non-conductive contact post mounted on the base, a stationary conductive contact mounted on the contact post, a conductive contact spring mounted on the plate, an integral conductive contact arm on the contact spring and slidably engaged with the stationary conductive contact.

References Cited in the file of this patent UNITED STATES PATENTS 2,617,912 Colvin Nov. 11, 1952 2,759,081 Mounteer Aug. 14, 1956 2,807,693 Scagnelli Sept. 24, 1957 2,845,514 Senseney July 29, 1958 blah 

